xtensa: mmu: arch_buffer_validate is only for user thread

arch_buffer_validate() is only to verify that user threads have
access to the memory region. It should not be used to verify
if kernel thread has access (which they should anyway). So
change the logic.

Signed-off-by: Daniel Leung <[email protected]>

Author: dcpleung

arch/xtensa/core/ptables.c

@@ -1083,8 +1083,7 @@ int arch_buffer_validate(const void *addr, size_t size, int write)
 	size_t aligned_size;
 	const struct k_thread *thread = _current;
 	uint32_t *ptables = thread_page_tables_get(thread);
-	uint8_t ring = ((thread->base.user_options & K_USER) != 0) ?
-		XTENSA_MMU_USER_RING : XTENSA_MMU_KERNEL_RING;
+	uint8_t ring = XTENSA_MMU_USER_RING;
 
 	/* addr/size arbitrary, fix this up into an aligned region */
 	k_mem_region_align((uintptr_t *)&virt, &aligned_size,